AS-OCT Study of Cornea and Tear Film Parameters in SLE Patients

Systemic lupus erythematous (SLE) is a relapsing and remitting autoimmune connective tissue disorder that can affect many organs such as skin, joints, kidneys, eye, and brain (1) . SLE has a global prevalence of 0.3 to 23.2 cases per 100,000. Women are more likely than men to develop the disease. Four out of the following 11 diagnostic criteria are sufficient for the diagnosis of SLE, malar rash, discoid rash, oral ulcers, non-erosive arthritis, serositis, photosensitivity, renal disorder, neurological disorder, hematological disorder, immunological disorder, and presence of antinuclear antibodies. (2,3)

Ocular manifestations occur in about one third of SLE patients with keratoconjunctivitis sicca being the most common manifestation which is characterized by decreased tear film aqueous layer. Scleritis, retinal vasculitis (which is often associated with CNS lupus), and papillitis are considered as the most serious ocular manifestations. (4)

Corneal involvement in SLE affects the superficial epithelium, resulting in superficial punctate keratitis, which is believed to be caused by Sjögren's syndrome (SS). However, some cases of non-infiltrative and infiltrative peripheral ulcerative keratitis have been identified (5) .

Schirmer's test and fluorescein breakup time test (FBUT) are two common clinical tests used to analyze tear film. (6,7) Using an in vivo, non- contact technique, anterior segment optical coherence tomography (AS- OCT) is now used to image the tear film, measure the lower tear film height and area, measure corneal thickness (pachymetry), and measure surface epithelial thickness. (8,9)

Inclusion criteria

• Age ≥18 years old..
• Patients with SLE diagnosed by a rheumatologist with no ocular involvement upon clinical examination

Exclusion criteria

• 1. Patients with history of intraocular surgery as cataract surgery ,retinal detachment surgery, anti-glucoma surgery.

• Patients with history of any corneal refractive surgery as LASIK, PRK. 3. Patients with significant media opacity as corneal opacity, cataract. 4. Patients with ocular diseases as glaucoma, uveitis. 5. Patients with any retinal affection as pathological myopia, macular hole, age related macular degeneration and retinal vascular occlusion.

• Patients with systemic diseases as diabetes mellitus, hypertension, abnormal kidney function.